static method can be called even if the instance of class is not created. Since they are loaded at the time of class creation. So if you override static method by non static method , which can be called by creating instance of object. does it make since to override it? As a good programming practice. We should not use static method until it is required. Might be this one of the reason they are imposing such rule.

The soul is dyed the color of its thoughts. Think only on those things that are in line with your principles and can bear the light of day. The content of your character is your choice. Day by day, what you do is who you become. Your integrity is your destiny - it is the light that guides your way. - Heraclitus